The key to perfect Frikadellen is the right mix and consistency. The soaked bread is essential for keeping the patties moist and adding a lightness to the meat mixture. Don't be afraid to be generous with the seasoning, as the meat needs a strong flavor to stand up to the richness.
Soak the bread roll in milk for a few minutes until it is soft. Squeeze out the excess milk and place the bread in a large bowl.
Add the ground meat, egg, chopped onion, breadcrumbs, mustard, salt, and pepper to the bowl. Mix everything thoroughly with your hands until a homogeneous and sticky mixture forms. Do not mix for too long, as the meat can become tough.
Moisten your hands with cold water to prevent the mixture from sticking. Shape the mixture into 8-10 oval patties (frikadellen), about 1.5 cm thick. The patties should be compact but not overly compressed.
In a pan over medium heat, heat the oil or lard. Carefully place the patties in the pan and fry them for 5-7 minutes on each side, or until they are golden brown and cooked through. If necessary, fry them in batches to avoid overcrowding the pan.
Serve the Frikadellen hot. They are excellent with mashed potatoes and braised onions, potato salad, or simply with bread and horseradish or mustard. They can also be eaten cold as part of a picnic or snack.